Sunday, March 8, 2015

The major focus of this blog is fossil marine vertebrates, but my secondary research interest is taphonomy - the study of fossil preservation. For a number of reasons, the preservation of terrestrial organisms is much better understood and more frequently studied than that of marine organisms. Many who dabble in marine taphonomy come at it from a background in marine vertebrate paleontology, or perhaps from nonmarine taphonomy; the body of knowledge available to us in this field is sort of cobbled together and no good summary articles really exist for the novice. People die in the ocean and wash up on beaches all the time - but surprisingly, the focus on studying forensic taphonomy in marine settings is even proportionally smaller than the marine taphonomic focus within paleontology. When one comes from an auxiliary discipline, it's easy to miss some of the more recently published, relevant articles in marine vertebrate taphonomy. So, to help out anyone with an interest in the preservation of marine vertebrates - here's a (hopefully) comprehensive list of publications from the past 5 years that you may not have noticed. If there is something that I've missed, I want to know! I'd love to include it. Abstracts are copied/pasted below as well.

Different
traces occur on fossil bones and teeth coming from the Early Miocene Gaiman
Formation (Patagonia, Argentina).
Most traces were attributed to the action of terrestrial and marine predators
and scavengers. However, other traces on bones and teeth from this unit and one
tooth from the Eocene La Meseta Formation (Antarctica)
are attributed to chemical corrosion by lichens in recent times, that is, in a
very late diagenetic time. The living lichens and calcium oxalate deposits
occurring on the traces and their particular pattern indicates that they were
not produced by vegetal roots. The lichens include reproductive structures
which allowed a proper determination. A kind of corrosion pattern (Type 1) on
bones and teeth from Patagonia is associated to Sarcogyne
orbicularis Korber, Verrucaria sp. Schrad, and Buellia aff.
punctiformis (Hoff.) Massal. The lichen Aspicilia aff. aquatica produced
rounded holes on an Antarctic tooth (Type 2). On the same tooth, the epilithic
lichen Caloplaca sp. Th. Fries did not leave any kind of mark on the
enameloid.

Decomposition
and faunal colonization of a carcass in the terrestrial environment has been
well studied, but knowledge of decomposition in the marine environment is based
almost entirely on anecdotal reports. Three pig carcasses were deployed in Saanich
Inlet, BC, over 3 years
utilizing Ocean Network Canada’s
VENUS observatory. Each carcass was deployed in late summer/early fall at 99 m
under a remotely controlled camera and observed several times a day. Dissolved
oxygen, temperature,
salinity, density and pressure were continuously measured. Carcass 1 was
immediately colonized by Munidaquadrispina, Pandalusplatyceros
and Metacarcinusmagister, rapidly scavenged then dragged from
view by Day 22. Artifacts specific to each of the crustaceans’ feeding patterns
were observed. Carcass 2 was scavenged in a similar fashion. Exposed tissue
became covered by Orchomenellaobtusa (Family Lysianassidae)
which removed all the internal tissues rapidly. Carcass 3 attracted only a few M.
quadrispina, remaining intact, developing a thick filamentous sulphur
bacterial mat, until Day 92, when it was skeletonized by crustacea. The major
difference between the deployments was dissolved oxygen levels. The first two
carcasses were placed when oxygen levels were tolerable, becoming more anoxic.
This allowed larger crustacea to feed. However, Carcass 3 was deployed when the
water was already extremely anoxic, which prevented larger crustacea from
accessing the carcass. The smaller M. quadrispina were unable to break
the skin alone. The larger crustacea returned when the Inlet was re-oxygenated
in spring. Oxygen levels, therefore, drive the biota in this area, although
most crustacea endured stressful levels of oxygen to access the carcasses for
much of the time. These data will be valuable in forensic investigations
involving submerged bodies, indicating types of water conditions to which the
body has been exposed, identifying
post-mortem artifacts and providing realistic expectations for recovery divers
and families of the deceased.

Probable
fossil ambergris occurs within early Pleistocene shallow-marine clay deposits
in western Umbria (central Italy).
More than 25 large, permineralized structures are scattered over an area of
~1200 m2. These are commonly convex to elongated, helicoidal to concentric,
calcium carbonate–rich structures, 30–60 cm high and 60–120 cm wide.
Permineralized squid beaks and altered organic matter occur inside these
structures. Preliminary chemical data reveal the presence of organic molecules
compatible with the degradation of cellular lipids, whose cholic acids indicate
the presence of mammalian gastric or intestinal activity; eight free amino
acids were also found. The results allow the identifi cation of these
structures as intestinal products of sperm whales living ~1.75 m.y. ago. The
described fossil structures represent the only known example of Pleistocene
sperm whale coprolites.

Barnes,
K.M., and Hiller, N. 2010. The taphonomic attributes of a Late Cretaceous
plesiosaur skeleton from New Zealand.
Alcheringa 34:333-344.

The
pre-burial history of a partial elasmosaurid plesiosaur skeleton is
reconstructed from analysis of the distribution and modification of bones
preserved in a calcareous concretionary mass. The specimen lacks the skull,
cervical vertebrae, left limb bones and some girdle elements, but the remaining
bones are interpreted to have been deposited on the sea floor from a
semi-buoyant carcass and their relative positions modified by the action of
scavengers. Bioerosive agents caused loss of bone, particularly on joint
surfaces and vertebral centra, as the carcass lay exposed on
the sea floor, perhaps for several years before burial.

A taphonomic model is erected for a dataset of 19 Steneosaurus
(Mesoeucrocodylia; Thalattosuchia) from the Toarcian Posidonienschiefer
Formation (Lower Jurassic) of Germany. These were deposited in a quiet-water, marine, basin.
Their taphonomy is compared with that of an additional seven thalattosuchians
from other Jurassic localities (Peterborough and Yorkshire, UK; Nusplingen, Germany). The skeletal taphonomy of the specimens is assessed in
terms of the articulation and completeness of nine skeletal units. Steneosaurus
from the Posidonienschiefer Formation exhibit variable levels of articulation in the nine
units. Completeness also varies but the head, neck and dorsal units are
complete in all specimens. Carcasses reached the sediment–water interface
shortly after death. Loss of fidelity occurred primarily as individuals lay on
the sediment, and disarticulated elements tended to remain in the vicinity of the
carcass. Those elements absent from specimens are the smaller, more distal, bones
of the limbs and tail; these were removed preferentially by weak bottom
currents. Smaller specimens are consistently less complete. Specimens from other
localities broadly follow the same taphonomic pathway, suggesting a consistent
pattern for the skeletal taphonomy of the carcasses of marine crocodiles. Loss
of completeness in some specimens is more exacerbated, the result of stronger
current activity at the sediment–water interface.

Taphonomic
models for fossil vertebrates are designed to reconstruct processes that
affected carcasses during the transition from biosphere to geosphere, in
particular in the interval between death and burial. To circumvent various
limitations in existing methodologies, a new taphonomic method, assessing
vertebrate skeletons as nine anatomical units (the head, neck, dorsal, tail,
ribs and four limbs) scored independently for two characters (articulation and
completeness), was developed. The potential of the method is demonstrated using
the Triassic marine reptile Serpianosaurus from Monte San Giorgio, Switzerland.
Specimens are preserved in alternations of black shale and dolomite,
representing normal background sediment and event beds respectively, deposited
into a shallow, intra-platform basin. All specimens exhibit disarticulation of
skeletal elements though loss of completeness varies
considerably.Minor loss of fidelity occurred during the ‘floating phase’, but
individuals reached the sediment-water interface relatively soon after death,
and largely intact, where they decayed during the ‘residence phase’. Carcasses
allowed to reach extensive states of decay became prone to the effects of weak
bottom currents, resulting in removal of elements. The episodic deposition of
event beds rapidly buried individuals at various stages of decay, inhibiting
further disarticulation and loss of completeness.

Becker,
M.A., and Chamberlain, J.A. 2012. Squalicorax chips a tooth: A
consequence of feeding-related behavior from the lowermost Navesink Formation

Chipped
and broken functional teeth are common in modern sharks with serrated tooth
shape. Tooth damage consists of splintering, cracking, and flaking near the
cusp apex where the enameloid is broken and exposes the osteodentine and
orthodentine. Such
damage is generally viewed as the result of forces applied during feeding as
the cusp apex impacts the skeletal anatomy of prey. Damage seen in serrated functional
teeth from sharks Squalicorax kaupi [1] and Squalicorax pristodontus [1]
from the late Cretaceous lowermost Navesink Formation of New Jersey resembles
that occurring in modern sharks and suggests similar feeding behavior. Tumbling
experiments using serrated modern and fossil functional shark teeth, including
those of Squalicorax, show that teeth are polished, not cracked or
broken, by post-mortem abrasion in lowermost Navesink sediment. This provides
further evidence that chipped and broken Squalicorax teeth are
feeding-related and not taphonomic in origin. Evolution of rapid tooth
replacement in large sharks such as Squalicorax ensured maximum
functionality after feeding-related tooth damage occurred. Serrated teeth and
rapid tooth replacement in the large sharks of the Mesozoic and Cenozoic
afforded them competitive advantages that helped them to achieve their place as

A new
finding of a marine mammal is documented from the middle Miocene of El Camp
basin in Tarragona (NE
Spain). The incomplete and disarticulated bone remains belong to
the skeleton of a juvenile cetacean. These remains appear deposited above a
transgression surface and included within a glauconitic calcisiltite layer.
This unit constitutes the beginning of a shallowing-upwards sequence and was
deposited under low energy conditions and low sedimentation rates in a
middle-outer platform setting. This context was responsible for the long
exposure of the remains and, consequently, an extension of the biostratinomic
stage. These conditions favored the natural decomposition and disarticulation
of the carcass, allowing the action of different types of scavenging organisms.
The interpretation of the paleoenvironmental setting is based in the
combination of different datasets: taphonomic data of the bone remains,
paleoecologic and taphonomic information provided by the fauna associated to
the bones, and ichnologic and sedimentologic interpretation of the sediments
where the fossils are included. Combination of such different proxies enables a
very good characterization of the paleoenvironmental context of the studied
fossils.

Clavate
borings found in the tympanic bulla of a Miocene cetacean from El Camp de
Tarragona Basin constitute the first evidence of the ichnogenus Gastrochaenolites
in bones of an autochthonous cetacean carcass. Previous records of similar
trace fossils on marine bones were described from transported or reworked
remains. Based on their morphology and ichnotaxonomy, the borings are assigned
to the activity of pholadid bivalves, which would have colonized the skeletal
carcass on the sea floor after removal of covering soft tissues.
Sedimentological and paleontological data indicate a low-energy depositional
setting with low sedimentation rate, which would have provided the temporal
window for bivalve colonization. This new finding contributes to widen our
knowledge of bioerosion in marine vertebrate skeletons.

A new
protocetid archaeocete, Aegyptocetus tarfa, is represented by a nearly
complete cranium and an associated partial skeleton. The specimen was recovered
when marbleized limestone was imported commercially to Italy
and cut into decorative facing stone. It came from middle Eocene Tethyan marine
strata of the Gebel Hof Formation of Wadi Tarfa in the Eastern Desert of Egypt.
Exceptional preservation and preparation enables study of some internal
features of the skull as well as its external morphology. The skull of Aegyptocetus
is unusual in having the rostrum and frontal portions of the cranium
deflected more ventrally relative to the braincase than is typical for
archaeocetes. This ventral deflection, clinorhynchy, is a rare specialization
related to feeding or hearing that is widely distributed across mammals. Aegyptocetus has
well-developed ethmoidal turbinal bones, indicating retention of a functional
sense of smell. It also has cranial asymmetry, thinning of the lateral walls of
the dentaries, enlarged mandibular canals, and thinning of the anterolateral
walls of the tympanic
bullae, indicating enhanced ability to hear in water. Neural spines are long on
thoracic vertebrae T1 through T8, suggesting that Aegyptocetus was able
to support its weight on land like other protocetids. This combination of
terrestrial and aquatic
characteristics is consistent with interpretation of protocetids as
semiaquatic. The pattern of tooth marks preserved on the ribs of Aegyptocetus
indicates that the individual studied here was attacked by a large shark,
but it is not certain whether

Shark
bite marks, including striae, sulci and abrasions, in a well-preserved fossil
dolphin skeleton referred to Astadelphisgastaldii (Cetacea, Delphinidae)
from Pliocene sediments of Piedmont (northern Italy), are described in detail.
The exceptional combination of a fossil dolphin having a significant part of
the skeleton preserved and a large number of bite marks on the bones represents
one of the few detailed
documentations of shark attack in the past. Most bite marks have been referred
to a shark about 4 m long with unserrated teeth, belonging to Cosmopolitodushastalis, on the basis of their shape and their general disposition on
the dolphin skeleton. According to our hypothesis, the shark attacked the
dolphin with an initial mortal bite to the abdomen from the rear and right, in
a similar way as observed for the
living white shark when attacking pinnipeds. A second, less strong, bite was
given on the dorsal area when the dolphin, mortally injured, probably rolled to
the left. The shark probably released the prey, dead or dying, and other sharks
or fishes probably scavenged the torn body of the dolphin.

Fossils
of extinct fur seals and walruses (Carnivora: Pinnipedia) occur within rich
vertebrate fossil assemblages recovered from the shallow marine Mio-Pliocene
Purisima Formation, central California.
Two isolated postcranial bones—a humerus and a radius—belonging to a juvenile
fur seal (Pinnipedia: Otariidae) exhibit circular depressions. These bone
modifications are associated with radial and circular fractures, and are
characterized by inward displacement of the cortex. These depressions lack
features typical of erosive invertebrate borings, trampling damage from media
(5substrate) interaction, puncturing by another object during diagenetic
compaction, such as a clast embedded or associated with the modification, or
pathologic bone modification. These features are best interpreted as tooth
marks. These tooth marks lack certain characteristics of commonly reported
marks inflicted by shark teeth, such as linear gouges and subparallel scrapes
formed by xiphodont

and
serrated teeth. These bone modifications instead exhibit a circular shape and
inward displacement of the cortex, consistent with puncturing by a conical
mammal tooth. The size and distribution of the tooth marks, in concert with the
known vertebrate assemblage from the Purisima Formation, indicate several
possible producers of the bone modifications: a pilot whale or beluga-like
cetacean, a terrestrial carnivore, a dusignathine or odobenine walrus, or a
case of infanticide by a conspecific otariid.

Fossil
evidence of barnacle encrustation of vertebrate bones is reported from the
middle Pleistocene Port Orford Formation of southern coastal Oregon.
This material includes two associated thoracic vertebrae and a femur referable
to the extinct sea lion Proterozetesulysses that are encrusted
by 1400 individual barnacles (cf. Hesperibalanushesperius), and
a scapula of Zalophuscalifornianus with barnacle attachment
scars. In areas, the encrusting barnacles exhibit a roughly bimodal size range,
and small barnacles are observed directly encrusting other larger individuals.
The size, probable age, and lifespan of extant Hesperibalanushesperius
indicates a minimum period of four to seven months of seafloor exposure between
decomposition and burial, although this estimate must be longer because at
least two colonization events are represented. Barnacle attachment traces are
identified as Anellusichnuscircularis. The wide distribution of
barnacles on some of these bones suggests these were regularly overturned by
bottom currents, which would prevent barnacles from being smothered by
prolonged contact with the sediment. Detailed study of barnacle-induced trace
fossils on these specimens suggests that episkeletozoans and their traces can
be useful sources of data regarding the biostratinomic history of vertebrate
fossils.

Boessenecker, R.W. and Fordyce, R.E. 2014. Trace fossil
evidence of predation upon bone-eating worms on a baleen whale skeleton from
the Oligocene of New Zealand. Lethaia DOI: 10.1111/let.12108.

The
osteophagous worm Osedax (Annelida: Siboglinidae) colonizes vertebrate
bones in
deep-sea environments globally. Osedax bioerosion of modern bones
suggests a potentially
destructive agent in the marine vertebrate fossil record, but the dearth of published
reports of abundant Osedax traces suggests an uncertain taphonomic
influence of this organism. This study reports Osedax traces (Osspecus
boreholes, pockmarks and collapsed galleries) in an Oligocene baleen whale
(Cetacea: Eomysticetidae) from New Zealand,
which constitute the first record of fossil Osedax traces from the southern
hemisphere. Some Osedax traces are cross-cut by linear biogenic scrape marks,
implying that sharks or bony fish fed upon Osedax worms, a process which
compounds or potentially accelerates worm-inflicted damage to vertebrate bones
in marine environments.

Background:
Taphonomic study of marine vertebrate remains has traditionally focused on
single skeletons, lagerstatten, or bonebed genesis with few attempts to
document environmental gradients in preservation. As such, establishment of a concrete
taphonomic model for shallow marine vertebrate assemblages is lacking. The
Neogene Purisima Formation of Northern California, a richly fossiliferous unit
recording nearshore to offshore depositional settings, offers a unique opportunity
to examine preservational trends across these settings. Methodology/Principal
Findings: Lithofacies analysis was conducted to place vertebrate fossils within
a hydrodynamic and depositional environmental context. Taphonomic data
including abrasion, fragmentation, phosphatization, articulation, polish, and
biogenic bone modification were recorded for over 1000 vertebrate fossils of
sharks, bony fish, birds, pinnipeds, odontocetes,
mysticetes, sirenians, and land mammals. These data were used to compare both
preservation of multiple taxa within a single lithofacies and preservation of
individual taxa across lithofacies to document environmental gradients in preservation.
Differential preservation between taxa indicates strong preservational bias
within the Purisima Formation. Varying levels of abrasion, fragmentation,
phosphatization, and articulation are strongly correlative with physical
processes of
sediment transport and sedimentation rate. Preservational characteristics were
used to delineate four taphofacies corresponding to inner, middle, and outer
shelf settings, and bonebeds. Application of sequence stratigraphic methods shows
that bonebeds mark major stratigraphic discontinuities, while packages of rock
between discontinuities consistently exhibit onshore-offshore changes in
taphofacies. Conclusions/Significance:
Changes in vertebrate preservation and bonebed character between lithofacies
closely correspond to onshore-offshore changes in depositional setting,
indicating that the dominant control of preservation is exerted by physical
processes. The strong physical control on marine vertebrate preservation and
preservational bias within the Purisima Formation has implications for
paleoecologic and paleobiologic studies of marine vertebrates. Evidence of preservational
bias among marine vertebrates suggests that careful consideration of taphonomic
overprint must be undertaken before meaningful paleoecologic interpretations of
shallow marine vertebrates is attempted.

Buckeridge, J.S. 2011. Taphonomy and systematics of a new
Late Cretaceous verrucid barnacle (Cirripedia, Thoracica) from Canterbury,
New Zealand.
Palaeontology 54:365-372.

Cirripede
remains (Thoracica, Verrucomorpha), found associated with the mosasaur Prognathodon
waiparaensis Welles and Gregg, 1971 in glauconitic sands of the Late Cretaceous
Conway Formation exposed along the Waipara River bank (mid-Canterbury, New
Zealand), are identified as a new species, Verruca sauria sp. nov. On
the basis of taphonomy, it is deduced that these verrucids grew on a postmortem
accumulation of mosasaur bones under very quiescent conditions. The current
amphitropical distribution of the earliest known verrucids, i.e. V. sauria sp.
nov., V. prisca Bosquet, 1854, V. pusilla Bosquet, 1857 and V.
tasmanica Buckeridge, 1983, is rationalized in the light of Tethyan palaeogeography.

The Upper Kimmeridgian Wattendorf Plattenkalk, the oldest
of the Solnhofen-type plattenkalks of southern Germany, has yielded a high number of exceptionally preserved fossils over the past several years. The high number
of fossils and the fact that every bedding plane, along which the laminated
rocks split, has been equally thoroughly searched for fossils, allow for qualitative as
well as quantitative taphonomic investigations. For a quantitative analysis of
the Wattendorf lagerstätte, four different taphofacies (A–D) were established
by means of euclidean cluster analysis. For this, biostratinomic features of
neopterygian fishes, primarily of the genus Tharsis, were recorded. Percentages
of the occurrence of these features per layer were determined and clustered
into groups of similar patterns. The taphonomic features utilised were bending
of the spinal column, completeness, and skeletal articulation. Taphofacies A
through D mark a change from a palaeoenvironment with only small extrinsic disturbing factors to a
palaeoenvironment characterised by greater disturbance (e.g. bottom currents, fluctuating
salinity). At the beginning of plattenkalk deposition, cyclic changes of the
palaeoenvironment prevailed with periodic high disturbance, probably caused by
storminduced flows. These events initiated mixing of the supposedly chemically
stratified water body. In the upper part of the plattenkalk unit, taphofacies
indicative of higher disturbance dominate, suggesting a change from stable to
less stable environmental conditions in the plattenkalk basin resulting in disruption
of the typical plattenkalk sedimentation. Sporadic oxygenation of bottom waters
is also indicated by the style of soft-tissue preservation. Besides typical
phosphatisation, a specimen of Palaeohirudo? sp. shows soft-tissue preservation
through iron-oxide permineralisation.

Several
traces of biological interaction were found on penguin bones from the basal
levels (Aquitanian) of the Miocene Gaiman Formation in the lower Chubut
valley of the Provincia del Chubut, Argentina.
The fossil-bearing beds were deposited in littoral to sublittoral environments
within sediments of mostly pyroclastic origin. We interpret many traces to have
been produced by predators and/or scavengers while the penguins were still in a
breeding area. Many bones show cracking marks due to aerial exposure. The
material is disarticulated as is usual in recent breeding areas. Potential
predators were coeval terrestrial mammals, most probably marsupial carnivores.
After a marine transgression, these bones were buried or exposed on the sea
bottom where they could be colonized by algae, sponges, cnidarians, and other
benthic organisms. We identified sponge borings in several bones. Other traces
are interpreted to have been produced by echinoderms feeding on sponges or
algae. No evidence of other invertebrate predators such as muricid or naticid
gastropods, or decapods was found. Finally, other traces appear to have been generated
by shark and possibly teleostean vertebrates feeding on epibionts. One coracoid
is interpreted to have been marked by a shark that is common in the Gaiman
Formation, the carcharhiniform Galeocerdoaduncus. From an ethological
(Seilacherian) classification, traces on bones from the Gaiman Formation
include Domichnia (sponge perforations), Praedichnia (terrestrial
marsupials, sharks, teleosteans) and Pasichnia (echinoderms).
Remarkably, remains of marine organisms with skeletons made of calcium
carbonate are very poorly preserved in the Gaiman Formation. Only large
oysters, sparse shell fragments, skeletal moulds, and bioturbation is evident.
The fossil assemblage is mainly composed of phosphatic (e.g. teeth, bones,
crustacean parts) and siliceous (sponge spicules, diatoms) remains.

The fossil bones, associated carbonate cements and
enclosing concretion of a Miocene mysticete from inner shelf deposits (Monte
Vallassa Formation, northern Italy) were analyzed for evidence of microbial activity. Optical
and scanning electron microscopy, Raman spectroscopy, and stable C and O
isotope geochemistry were used for high spatial resolution microfacies and
biosedimentological analyses. Whale cancellous bones were filled by different
carbonate cements including microcrystalline dolomite, rhombohedral dolomite and
sparry calcite. Biofabric and biominerals such as microbial peloids, clotted
textures and pyrite framboids were associated with the dolomite cements.
Dolomite inside cancellous bones and in the enclosing concretion showed similar
isotopic values (avg δ13C: −7.12‰; avg δ18O: +3.81‰), depleted with respect to
the (late) sparry calcite cement (avg δ13C: −0.55‰; avg δ18O: −0.98‰).
Microcrystalline barite (BaSO4) was observed on the external surface of the
bones. In addition, two different types of microborings were recognized, distinguished
by their size and morphology and were ascribed respectively to prokaryote and
fungal trace makers. Our results testify for the development of a diverse
microbial ecosystem during the decay of a shallow water whale carcass, which
could be detected in the fossil record. However, none of the observed biosignatures
(e.g., microbial peloids, clotted textures) can be used alone as a positive
fossil evidence of the general development of a sulfophilic stage of whale fall
ecological succession. The occurrence of the hard parts of chemosynthetic
invertebrates associated with fossil whale bones is still the more convincing
proof of the development of a sulfide-base chemoautotrophic ecosystem.

Twenty-five
Neogene–Quaternary whales hosted in Italian museum collections and their
associated fauna were analysed for evidence of whale-fall community development
in shallow-water settings. The degree of bone articulation, completeness of the
skeleton and lithology of the embedding sediments were used to gather
information on relative water depth, water energy, sedimentation rate and
overall environmental predictability around the bones. Shark teeth and
hard-shelled invertebrates with a necrophagous diet in close association with
the bones were used as evidence of scavenging. Fossil bone bioerosion,
microbially mediated cementation and other mollusc shells in the proximity of
the remains informed on past biological activity around the bones. The results
are consistent with the hypothesis that shallow-water whale falls differ from
their deep-water counterparts. Taphonomic pathways are more variable on the
shelf and whale carcasses may not go through all steps of the ecological
succession as recognised in the deep sea. Whilst the mobile scavenger and the
enrichment opportunistic stages are well represented, chemosynthetic taxa
typical of the sulphophilic stage were recovered only in one instance. The
presence of a generalist fauna among the suspension feeding bivalves and
carnivorous gastropods, and the extreme rarity of chemosynthetic taxa, suggest
that predatory pressure rules out whale-fall specialists from shallow shelf
settings as in analogous cold seep and vent shallow-water communities.

After
the discovery of whale fall communities in modern oceans, it has been
hypothesized that during the Mesozoic the carcasses of marine reptiles created
similar habitats supporting long-lived and specialized animal communities.
Here, we report a fully documented ichthyosaur fall community, from a Late Jurassic
shelf setting, and reconstruct the ecological succession of its micro- and
macrofauna. The early ‘mobile-scavenger’ and ‘enrichment-opportunist’ stages
were not succeeded by a ‘sulphophilic stage’ characterized by chemosynthetic
molluscs, but instead the bones were colonized by microbial mats that attracted
echinoids and other mat-grazing invertebrates. Abundant cemented suspension
feeders indicate a well-developed ‘reef stage’ with prolonged exposure and
colonization of the bones prior to final burial, unlike in modern whale falls
where organisms such as the ubiquitous bone-eating worm Osedax rapidly
destroy the skeleton. Shallow-water ichthyosaur falls thus fulfilled similar
ecological roles to shallow whale falls, and did not support specialized chemosynthetic
communities.

Diedrich,
C.G., and Felker, H. 2012. Middle Eocene shark coprolites from shallow marine
and deltaic coasts of the pre-North Sea
Basin in central Europe.
New Mexico Bulletin of Natural
History and Science 57:311-318.

Middle Eocene
(Paleogene, Cenozoic) transgressive marine conglomerates of two German
localities in the southern Pre-North Sea basin of Central Europe contain a
large number of more then 19 different large- to medium-sized shark taxa (teeth
size > 4 mm). Only 0.05% of the vertebrate remains are shark coprolites (n =
556), which can be classified in five main types, most having a
heteropolar-spirally-coiled morphology. These are classified into five
different main shape types. Possibly the largest forms (Type A), in part
containing medium sized fish bones and vertebrae, belong to megatooth and white
shark ancestors (Otodus, Carcharocles, Procarcharodon), whereas
the most abundant, medium-sized variable forms (Type B) might have been
produced by laminid sharks (Isurus, Jaeckelotodus, Xiphodolamia, Brachycarcharias, Hypotodus, Sylvestrilamia), but the
very abundant sand shark ancestor Striatolamia is
expected as their main producer. Type C is rare and a thin elongated form with
zigzag-heteropolar external structure (producers: ?rays/small-sized
carchariniform sharks such as Galeocerdo, Pachygaleus). The
smaller, including the smallest (only 3 mm) oval-round pellets, and also the
unclearly heteropolar Type D oval- to round-shaped pellets have only poorly
developed surface coil structures, and are preliminarily referred to sharks or
rays. Rare, irregularly-formed excrement can be referred preliminarily to a
crocodile producer, which supports the deltaic distal position of the Dalum
site, and more shallow marine position
of the Osteroden locality. At the latter, larger shark coprolites (Type A) are
much more abundant, indicating more shallow marine environments, whereas at
Dalum a mixture of shallow marine and deltaic palaeoenvironments were present
during the Middle Eocene of the southern Pre-North Sea Basin of Central Europe.

Coprolites (fossilized feces) preserve a wide range of
biogenic components, from bacteria and spores to a variety of vertebrate
tissues. Two coprolites from the Calvert Cliffs outcrop belt (Miocene-aged Chesapeake Group),
MD, USA, preserve shark tooth impressions in the form of partial
dental arcades. The specimens are the first known coprolites to preserve vertebrate tooth
marks. They provide another example of trace fossils providing evidence of
prehistoric animal behaviors that cannot be directly approached through the
study of body fossils. Shark behaviors that could account for these impressions
include: (1) aborted coprophagy, (2) benthic or nektonic exploration, or (3)
predation.

We
document an aspect of the marine paleoecology at Langebaanweg, a site that has
produced an abundance of vertebrate fossils. Damage to the bone surfaces of
cetacean fossils was not pathological as evident on the fossil seals from this
site; the current study documents the damage and attempts to provide a
parsimonious explanation. Literature reviews identified similar damage
described elsewhere to be the result of shark feeding activity. Comparison of
this material with Langebaanweg cetacean bones supports the interpretation that
the damage resulted from shark teeth. Damage on the various skeletal elements
appears to have been inflicted postmortem or, if they were made while the
animal was alive, the whales did not survive the attack. Postmortem damage is
also supported by the presence of bites on the dorsal, ventral, lateral, and medial
surfaces of a pair of dentaries. Bites were inflicted by sharks with serrated
teeth, as well as by sharks with unserrated teeth. Potential predators
identified from the marks include white (Carcharodon spp.), Zambezi
(bull) (Carcharhinus leucas), tiger (Galeocerdo sp.) and mako (Isurus
sp.) sharks.

Campanian
(Upper Cretaceous) shallow-marine strata of Asen, southern Sweden.
They are associated with a diverse vertebrate fauna and comprise at least seven
different morphotypes that suggest a variety of source animals. Their faecal
origin is corroborated by several lines of evidence, including chemical composition
(primarily calcium phosphate), external morphology and nature of the
inclusions. Preservation in a fossil coquina, interpreted as a taphocoenosis,
suggests early lithification promoted by rapid entombment. This would have
prevented disintegration of the faecal matter and facilitated transportation and
introduction to the host sediment. The coprofabrics can generally be correlated
to specific gross morphologies, supporting a morphology-determined coprolite
classification. Moreover, having been deposited under presumably comparable
taphonomic conditions, variations in coprofabrics infer differences in diet and
⁄ or digestive efficiency
of the host animal. Size and morphology of the coprolites imply that most, if
not all, were produced by vertebrates and the largest specimens infer a host
animal of considerable size. Two spiralled coprolite morphotypes yield bone
fragments and scales of bony fish, suggesting that the producers were
piscivorous sharks. Other coprolites contain inclusions interpreted as the
remains of shelled invertebrates, thus indicating that they may have derived
from durophagous predators and ⁄
or scavengers. The occurrence of small scrapes, tracks and traces on
several specimens suggest manipulation of the faeces by other (presumably
coprophagous) organisms after deposition. The collective data from the
Asen coprolites provide new insights into a shallow-water Late Cretaceous
marine ecosystem
hitherto known solely from body fossils.

Basilosauridae are cosmopolitan
fully-aquatic archaeocete whales, represented by larger Basilosaurus isis and
smaller Dorudon atrox in the middle-to-late Eocene Gehannam and Birket Qarun Formations of
Egypt (ca. 38-36.5 Ma). Adult and juvenile Dorudon but only adult Basilosaurus
are found in these shallow-marine deposits. Lethal bite marks on juvenile Dorudon
skulls sparked the idea that adult Basilosaurus invaded calving
grounds of D. atrox to prey on their young. However, there has been no
direct evidence to support this idea. In this study, bite marks on specimens of
juvenile D. atrox that have previously been described but not assigned
to a particular tracemaker are reinvestigated, and additional bone
modifications are analyzed. Applying computed tomography (CT), digital surface
scanning, and three-dimensional (3D) reconstruction, the juvenile D. atrox specimens
were digitally placed into the mouth of an adult B. isis. Bite marks
match the dentition of B. isis. Imprints of tooth casts of B. isis in
modeling clay furthermore resemble bite marks on these D. atrox specimens
in shape and size. B. isis was likely a predator that included juvenile D.
atrox in its diet. Prey was predominantly captured from a lateral position
across the head and sometimes adjusted in the mouth prior to a more powerful
bite. Scavenging of B. isis on D. atrox calves is also possible.
The diet of Basilosaurus and dietary differences within the genus
resemble those known in modern killer whales (Orcinus orca). B. isis is
the only archaeocete known to date that possibly preyed on other cetaceans.

The
Eocene vertebrates and their faunal communities present in Wadi El- Hitan -
Siwa area (Egyptian Western
Desert) indicate that they lived in
a semienclosed basin with an open outlet to the sea and fresh water from the
neighboring land. The ecological consequences of freshwater input and mixing
with marine water created strong gradients within suitable physicochemical
characteristics, biological activity and diversity. This type of ecological
niches represents the most productive one among all marine ecosystems. The
sheer quantity of fossils reflects the ample presence of various life forms
that existed in the sea-waters of the Eocene time in the Egyptian
Western Desert.
The richness and highly diversifiable fauna found at the exposures
of the studied area imposed our attention for studying and graphicalp
simulation of the palaeoenvironmental parameters that controlled the formation
of such assortment of organisms as well as the study of the taphonomic
management of these bone accumulations.

Chemosynthesis-based
communities have existed on whale skeletons for over 35 million years. However
little is known about the effects of Osedax boring on the bone taphonomy
and ecology of the whale-fall community. In order to evaluate this important
process we used micro computed-tomography (CT) to ascertain the morphology of
borings produced by Osedaxmucofloris on a Minke whale bone
exposed on the sea-floor for eight months. CT images revealed wide, shallow
sub-surface cavities where the roots eroded the bone. These cavities were
restricted to the densest layer of bone and had a maximum penetration of 2.63
mm. Over the eight month period 0.67% of the bone had been degraded directly by
Osedax borings. These findings suggest that the presence of Osedax
can lead to the rapid degradation of whale bones, having important implications
for the ecology of whale-fall communities. Furthermore, these descriptions
allow the potential identification of Osedax activity at fossil
whale-falls.

Osedax
worms possess unique “root” tissues that they use to bore into bones on the
seafloor, but details of the boring pattern and processes are poorly
understood. Here we use X-ray micro-computed tomography to investigate the
borings of Osedax mucofloris in bones of the minke whale (Balaenoptera
acutorostrata), quantitatively detailing
their morphological characteristics for the first time. Comparative
thin-sections of the borings reveal how the bone is eroded at the
sub-millimeter level. On the basis of these results we hypothesize a model of
boring that is dependent on the density and microstructure of the bone. We also
present evidence of acidic mucopolysaccharides in the mucus of the root tissue,
and hypothesize that this plays an
important role in the boring mechanism. We discuss the utility of these new
data in evaluating Osedax trace fossils and their relevance for O.
mucofloris ecology. Measured rates of bone erosion (6% per year) and
evidence of enhanced sulfide release from the borings indicate that Osedax worms
are important habitat modifiers in whale-fall communities.

Osedax
worms subsist entirely on vertebrate skeletons on the seafloor, using root-like
tissues to bore into and degrade the bones. Paleontologists have only recently
begun to appreciate the possible destructive effect that these worms may have
had on the marine vertebrate fossil record and little is known of their
evolutionary history. Using microcomputed tomography, we document Osedax-like
borings in a fossil whale bone from the Pliocene of Italy and present new data
on the borings of extant Osedax worms. The fossil borings are distinguished
from those of other known borers and identified as traces of Osedax
activity based on diagnostic features. Our results suggest that it is necessary
to isolate individual borings for the confident identification of Osedax
traces. This is only the second paleogeographic occurrence of Osedax in
the fossil record and indicates that by the Pliocene these worms had colonised
a large portion of the world’s oceans. This is the first evidence for Osedax
in the Mediterranean, past or present, and suggests that
more species await discovery in this region.

An
exhaustive screening of public collections containing remains of the latest
Cretaceous (late Maastrichtian) marine turtle Allopleuron hofmanni
(Gray, 1831) from the type area of the Maastrichtian Stage (southeast
Netherlands, northeast Belgium) shows the available material to represent
almost exclusively adult individuals. The various skeletal elements are not
preserved in proportionally equal abundance, with portions of carapace,
pectoral girdle, cranium and mandible overrepresented. These observations can
be explained by population characteristics and taphonomic factors. During the
late Maastrichtian, while hatchlings and juveniles in all likelihood lived and
fed elsewhere, extensive seagrass meadows might have supported a population of
only adult marine turtles.

Osedax
is a recently discovered group of siboglinid annelids that consume bones on the
seafloor and whose evolutionary origins have been linked with Cretaceous marine
reptiles or to the post-Cretaceous rise of whales. Here we present whale bones
from early Oligocene bathyal sediments exposed in Washington
State, which show traces similar to
those made by Osedax today. The geologic age of these trace fossils (~30 million years) coincides
with the first major radiation of whales, consistent with the hypothesis of an evolutionary
link between Osedax and its main food source, although older
fossils should certainly be studied. Osedax has been destroying bones
for most of the evolutionary history of whales and the possible significance of
this “Osedax effect” in relation to the quality and quantity of their
fossils is only now recognized.

The bone-eating marine annelid Osedax consumes mainly
whale bones on the deep-sea floor, but recent colonization experiments with cow
bones and molecular age estimates suggesting a possible Cretaceous origin of Osedax
indicate that this worm might be able grow on a wider range of substrates. The
suggested Cretaceous origin was thought to imply that Osedax could colonize
marine reptile or fish bones, but there is currently no evidence that Osedax
consumes bones other than those of mammals. We provide the first evidence that Osedax
was, and most likely still is, able to consume non-mammalian bones, namely bird
bones. Borings resembling those produced by living Osedax were found in
bones of early Oligocene marine flightless diving birds (family Plotopteridae). The species that
produced these boreholes had a branching filiform root that grew to a length of
at least 3 mm, and lived in densities of up to 40 individuals per square
centimeter. The inclusion of bird bones into the diet of Osedax has
interesting implications for the recent suggestion of a Cretaceous origin of
this worm because marine birds have existed continuously since the Cretaceous.
Bird bones could have enabled this worm to survive times in the Earth’s history
when large marine vertebrates other than fish were rare, specifically after the
disappearance of large marine reptiles at the end-Cretaceous mass extinction
event and before the rise of whales in the Eocene.

The
range of substrates that the bone-eating marine worm Osedax is able to
consume has important implications for its evolutionary history, especially its
potential link to the rise of whales. Once considered a whale specialist,
recent work indicates that Osedax consumes a wide range of vertebrate
remains, including whale soft tissue and the bones of mammals, birds and
fishes. Traces resembling those produced by living Osedax have now been
recognized for the first time in Oligocene whale teeth and fish bones from
deep-water strata of the Makah, Pysht and Lincoln Creek formations in western Washington
State, USA.
The specimens were acid etched from concretions, and details of the borehole
morphology were investigated using micro-computed tomography. Together with
previously published Osedax traces from this area, our results
show that by Oligocene time Osedax was able to colonize the same range
of vertebrate remains that it consumes today and had a similar diversity of
root morphologies. This supports the view that a generalist ability to exploit
vertebrate bones may be an ancestral trait of Osedax.

Loon,
A.J. van. 2013. Ichthyosaur embryos outside the mother body: not due to carcass
explosion but to carcass implosion. Palaeobiodiversity and Palaeoenvironments
93:103-109.

Some well-preserved ichthyosaurs found in the Early
Jurassic Posidonienschiefer Formation at Holzmaden (Germany) have puzzled palaeontologists for a long time: their skeletons are exceptionally well preserved and
their bones are almost all in situ, but the bones of their embryos are
scattered, partly beyond the body limits of themother. This has been explained
initially by bottom currents and later by a displacement of already disarticulated embryos during the
expulsion of putrefaction gases through the disrupted body wall of the mother.
It was postulated recently that this latter hypothesis is not tenable. It is
argued here that both hypotheses are not tenable in their original form, but
that carcass implosion may explain the various enigmatic features.

Terrestrial
and marine invertebrate organisms both leave records of their activities in

the
sediment in the form of trace fossils, at least during certain stages of their
ontogeny. In contrast, trace fossils produced by vertebrate organisms are
scarce, although terrestrial trace fossils provide exclusive insights into the
social behaviour of their producers. In the marine realm, vertebrate trace
fossils are relatively rare, difficult to identify and problematic to
interpret. However, in certain settings, observations on serendipitously
preserved and exposed trace fossils can shed light on the predatory behaviour
of marine vertebrates. In Miocene outer shelf to nearshore sandstones of the
Taliao Formation in NE Taiwan, large numbers of
bowl-shaped trace fossils can be observed. Morphology and size range (diameter
typically 10–30 cm, average depth around 10 cm) of these trace fossils agree
well with feeding traces of modern stingrays, and the trace fossil Piscichnuswaitemata, which has been attributed to bottom feeding rays. Stingrays
direct a jet of water from their mouths to excavate a bowl-shaped pit to expose
their prey. In the material filling the excavated bowl, broken pieces of two
other common trace fossils, Ophiomorpha and Schaubcylindrichnus,
are often found, and in a number of cases, vertical shafts of Ophiomorpha
surrounded by dispersed pieces of wall material have been observed. In
contrast, surrounding sediment rarely contains this kind of broken pieces of
wall material. These observations clearly indicate that stingrays specifically
targeted the producers of the trace fossils: thalassinoid crustaceans and
worms, respectively. The targeted predation of these relatively deep burrowers furthermore
suggests that the rays used their electroreceptive organs to locate the prey;
as such, direct targeting of buried prey only based on olfactory senses has
been shown to be ineffective in experiments with extant myliobatiform rays.

The
siliciclastic sequence of the Upper Devonian of Kurzeme, Western
Latvia, is

renowned
for abundant vertebrate fossils, including the stem tetrapods Obruchevichthys
gracilis and Ventastega curonica. During the first detailed
taphonomic study of the vertebrate assemblage from the Ogre Formation cropping
out at the Langs_ede Cliff, Imula River, abundant vertebrate remains have been
examined and identified as belonging to one psammosteid, two acanthodian and
three sarcopterygian genera; the placoderm Bothriolepis maxima dominates
the assemblage. Besides fully disarticulated placoderm and psammosteid plates,
separate sarcopterygian scales and teeth, and acanthodian spines, partly
articulated specimens including complete distal segments of Bothriolepis
pectoral fins, Bothriolepis head shields and sarcopterygian lower jaws
have been found. The size distribution of the placoderm bones demonstrates that
the individuals within the assemblage are of approximately uniform age.
Distinct zones have been traced within the horizontal distribution of the
bones. These linear zones are almost perpendicular to the dominant dip azimuth
of the cross-beds and ripple-laminae and most probably correspond to the
depressions between subaqueous dunes. Concavity ratio varies significantly
within the excavation area. The degree of fragmentation of the bones and disarticulation
of the skeletons suggest that the carcasses were reworked and slightly transported
before burial. Sedimentological data suggest deposition in a shallow marine environment
under the influence of rapid currents. The fossiliferous bed consists of a basal
bone conglomerate covered by a cross-stratified sandstone with mud drapes,
which is in turn overlain by ripple laminated sandstone, indicating the bones
were buried by the
gradual infilling of a tidal channel. All the Middle–Upper Devonian vertebrate
bonebeds from Latvia
are associated with sandy to clayey deposits and have been formed in a sea-coastal
zone during rapid sedimentation episodes, but differ in fossil abundance and degree
of preservation.

Dead
whale carcasses that sink to the deep seafloor introduce a massive pulse of
energy capable of hosting dynamic communities of organisms in an otherwise
food-limited environment. Through long- term observations of one natural and
five implanted whale carcasses in Monterey Canyon,
CA, this study suggests that: (1) depth and
related physical conditions play a crucial role in species composition; (2) the
majority of species in these communities are background deep-sea taxa; and (3)
carcass degradation occurs sub-decadally. Remotely operated vehicles (ROVs)
equipped with studio quality video cameras were used to survey whales during
0.8 to seven year periods, depending on the carcass. All organisms were
identified to the lowest possible taxon. Community differences among
whale-falls seemed to be most strongly related to depth and water temperature.
The communities changed significantly from initial establishment shortly after
a carcass’ arrival at the seafloor through multiple years of steady
degradation. The majority of species found at the whale-falls were background
taxa commonly seen in Monterey Bay.
While populations of species characterized as bone specialists, seep
restricted, and of unknown habitat affinities were also observed, sometimes in
great abundance, they contributed minimally to overall species richness. All
whale carcasses, shallow and deep, exhibited sub- decadal degradation and a
time-series of mosaic images at the deepest whale site illustrates the rapidity
at which the carcasses degrade.

Previous
studies of the sequence stratigraphic distribution of fossils have focused on
the record of relatively abundant marine invertebrates. Only a handful of
studies have examined how sequence stratigraphic architecture influences the
occurrence of vertebrates, particularly large and rare tetrapods. The Jurassic
Sundance Formation of the Bighorn Basin, Wyoming, USA, contains a rich suite of
invertebrate and vertebrate fossils, including large and rare marine reptiles,
and this allows the sequence stratigraphic controls on the distribution of
these groups to be compared. The Sundance Formation consists of four
depositional sequences, with the lower two being carbonate dominated and the
upper two siliciclastic dominated. Two incised valley fills are also present.
The presence of multiple depositional sequences and strongly erosional sequence
boundaries is the likely cause of the complicated lithostratigraphic
nomenclature of the Sundance. Invertebrates (mollusks and echinoderms) in the
Sundance conform to well-established patterns of occurrences, including strong
facies control and fossil concentrations at maximum flooding surfaces, in the
upper portion of parasequences, and within lags overlying sequence boundaries.
As expected from their rarity, marine reptiles (ichthyosaurs, plesiosaurs, and
pliosaurs) show a weaker connection to sequence stratigraphic architecture. Nonetheless,
they do display facies control and are found primarily in offshore mudstone,
rather than shoreface and estuarine sandstone. They are also more common at
hiatal surfaces, including a zone of concretions at the maximum flooding
surface and in lag deposits overlying sequence boundaries. These associations
suggest that sequence stratigraphic architecture may be a useful approach for
discovery of marine vertebrates and that sequence stratigraphic context should
be considered when making

paleobiological
interpretations of marine vertebrates as well as invertebrates.

Ambergrisichnus
alleronae igen. et isp. nov.
from early Pleistocene clay marine deposits of Umbria, central Italy is here described, and attributed to
cololites (evisceralites) of sperm whales. This interpretation is supported by
the following characteristics that are frequently identified in modern
ambergris including: internal organization of concentric structures, external
shape with converging striae and bulges (rognons), and inclusions of squid beaks. These
cololites were deposited in a relatively deep (100-150m) marine environment,
and the large number of structures in a restricted area is plausibly ascribed to
multiple death events of sperm whales. The description of A.
alleronae igen. et isp. nov.
is held by analysis of the taphonomic processes that took place after the sperm
whale carcasses reached the seabed and led to fossilization. The analysis of
benthic micro- and macrofauna found close to the studied structures provides
supplementary data, which support the reconstruction of palaeoecological and
palaeoenvironmental conditions comparable with those of the whale fall
communities. This work increases knowledge of vertebrate coprolites. Moreover,
this new information provides the data about the frequency of sperm whales in
the Tyrrhenian
Sea during
the early Pleistocene, and raises new questions about the causes of this
anomalous accumulation.

Obasi, C.C., Terry, D.O., Myer, G.H., and Grandstaff, D.E.
2011. Glauconite composition and morphology, shocked quartz, and the origin of
the Cretaceous(?) main fossiliferous layer (MFL) in southern New
Jersey, U.S.A. Journal of Sedimentary Research
81:479-494.

The
Main Fossiliferous Layer (MFL) is a concentration of vertebrate and
invertebrate fossils, 20 to 30 cm thick, preserved in a sequence of glauconitic
sand at or near the Cretaceous–Paleogene boundary in the New Jersey (USA)
coastal plain. Several hypotheses have been proposed to explain the origin and
age of the MFL, including: marine transgression and formation of lag deposits
of reworked bones and shells, formation of a condensed section and attritional
accumulation of fossil material, and catastrophic collapse of Late Cretaceous
ecosystems following the end-Cretaceous bolide impact at Chicxulub. We use new
data on glauconite morphology, concentrations, geochemistry, and presence of
shocked quartz, coupled with previous data on sedimentology, taphonomy, and rare-earth-element
geochemistry of fossil vertebrates to interpret the genesis of the MFL.
Glauconite concentration and maturity steadily increases from latest Cretaceous
sediments of the Navesink–New Egypt Formation, through the MFL and into the
Paleogene upper Hornerstown Formation, suggesting that marine transgression and
decreasing sedimentation rates were a factor in the formation of the
glauconite, but not the MFL. Rare earth-element patterns in fossil bones from
the MFL, which are acquired during fossilization, are different from those of Cretaceous
and Paleogene specimens, indicating that vertebrate remains in the MFL
fossilized in situ and were not reworked from older, underlying units.
Vertebrate fossils from the MFL are preserved as isolated to articulated
specimens. While isolated specimens would be common in a transgressive lag,
articulated specimens would not. Articulated specimens could be concentrated by
attritional accumulation along a defined surface during a period of slow
sedimentation, but the lack of a distinct increase in glauconite maturity or
concentrations of elements associated with heavy-mineral accumulations at the Navesink–New
Egypt–Hornerstown contact or MFL, which would be expected during a period of
reduced sedimentation, hiatus, or unconformity, are absent at the localities
studied. Shocked quartz was identified in a burrow fill directly beneath the MFL,
at the contact of the Navesink and Hornerstown formations. Clay clasts with
latest Cretaceous microfossils, along with reworked invertebrate fossils with
infills of latest Cretaceous sediment, have been recovered from the MFL. The
association of shocked quartz, mixture of isolated and articulated vertebrates
with distinct rare-earth signatures, lack of a punctuated period of increased
glauconite maturity, and presence of reworked Late Cretaceous invertebrates and
clay clasts with Late Cretaceous microfossils suggests that the MFL may
represent a thanatocoenosis that was the direct result of environmental
disturbance associated with the end-Cretaceous impact event at Chicxulub.

Stranded marine mammals are an important source of
information and biological samples on cetacean population. Nevertheless,
collecting stranding data remains opportunistic and its representativity must
be improved, both qualitatively and quantitatively. Drifts of small cetaceans
found by-caught in fishery observation projects and subsequently released dead
with a numbered tag fitted to the tail fluke were predicted by using the
Météo-France drift model MOTHY and allowed us to assess the proportion of dead
dolphins recovered by volunteers of the French stranding network. Only 8% of
dolphins were recovered ashore. The spatial representativity of strandings was
assessed by performing back-calculation of car-cass drift with the same model
in order to map the likely origin of stranded cetaceans. As a first step,
external visual criteria of time-after-death (as a proxy to drift duration)
were obtained from series of pho-tographs of dead small cetaceans maintained in
a floating cage for 40 days and from tagged by-caught dolphins recovered
stranded after a drift in real condition. Then, pictures of 242 stranded common
dolphins (Delphinus delphis) were used to establish the average
distribution of dolphin time-after-death in this area. Finally, 40 days-long
reverse drifts of the 829 common dolphins recorded in the winter months of
2004–2009 were weighted by the modelled distribution of time-after-death in
order to map the areas of likely origin. It appeared that most stranded common
dolphins recorded along the French Atlantic coast originated from the
continental shelf, mostly in the south of the Bay of Biscay.
These results open new perspective on the use of stranding data and biological
samples as sources of indicators in monitoring strategies.

Pyenson, N.D.
2010. Carcasses on the coastline: measuring the ecological fidelity of the
cetacean stranding record in the eastern North Pacific Ocean.
Paleobiology 36:453-480.

To
understand how well fossil assemblages represent original communities,
paleoecologists seek comparisons between death assemblages and their source
communities. These comparisons have traditionally used nearshore, marine
invertebrate assemblages for their logistical ease, high abundance, and
comparable census data from living communities. For large marine vertebrates,
like cetaceans, measuring their diversity in ocean ecosystems is difficult and
expensive. Cetaceans,

however,
often beach or strand themselves along the coast, and archived data on stranded
cetaceans have been recorded, in some areas, over several decades. If the
stranding record is interpreted as a death assemblage, then the stranding
record may represent a viable alternative for measuring diversity in living
communities on directly adjacent coastlines. This study assessed the fidelity
of the cetacean stranding record in the eastern North Pacific Ocean.
The living community in this region has

been
studied for over 100 years and, recently, extensive and systematic live
transect surveys using ship-based observing platforms have produced a valuable
source of live diversity data. Over this same period, the U.S. Marine Mammal
Stranding Program has collected and archived a record of cetacean strandings
along the U.S. Pacific coastline, providing an ideal death assemblage for comparison.
Using fidelity metrics commonly used in marine invertebrate taphonomy, I
determined that the stranding record samples the living cetacean community with
high fidelity, across fine and

coarse
taxonomic ranks, and at large geographic scales (.1000 km of coastline). The
stranding record is also richer than the live surveys, with live-dead ratios
between 1.1 and 1.3. The stranding record recovers similar rank-order relative
abundances as live surveys, with statistical significance. Also, I applied
sample-based rarefaction methods to generate collector’s curves for strandings
along the U.S. Pacific Coast to better evaluate the spatiotemporal
characteristics of the stranding record. Results

indicate
that saturation (i.e., sampling .95% assemblage) at species, genus, and family
levels occurs in less than five years of sampling, with families accumulating
faster than species, and larger geographic regions (i.e., longer coastlines)
accumulating taxa the most rapidly. The high fidelity of the stranding record,
measured both in richness and by ranked relative abundance, implies that
ecological structure from living cetacean communities is recorded in the death
assemblage, a finding that parallels marine invertebrate assemblages, though at
far larger spatial scales. These results have implications for studying
cetacean ecology in both modern and ancient environments: first, these results
imply that the stranding record, over sufficiently long time intervals, yields
a richer assemblage than using line transect methods, and faithfully records
aspects of community structure; and second, these results imply that
geochronologically well-constrained fossil cetacean assemblages might preserve ecologically
relevant features of community structure, depending on depositional and
taphonomic conditions.

Pyenson,
N.D. 2011. The high fidelity of the
cetacean stranding record: insights into measuring diversity by integrating
taphonomy and macroecology. Proceedings of the Royal Society B 278:3608-3616.

Stranded
cetaceans have long intrigued naturalists because their causation has escaped
singular explanations. Regardless of cause, strandings also represent a sample
of the living community, although their fidelity has rarely been quantified.
Using commensurate stranding and sighting records compiled from archived
datasets representing nearly every major ocean basin, I demonstrated that the
cetacean stranding
record faithfully reflects patterns of richness and relative abundance in
living communities, especially for coastlines greater than 2000 km and
latitudinal gradients greater than 48. Live–dead fidelity metrics from seven
different countries indicated that strandings were almost always richer than
live surveys; richness also increased with coastline length. Most death
assemblages recorded the same ranked relative
abundance as living communities, although this correlation decreased in
strength and significance at coastline lengths greater than 15 000 km,
highlighting the importance of sampling diversity at regional scales.
Rarefaction analyses indicated that sampling greater than 10 years generally
enhanced the completeness of death assemblages, although protracted temporal
sampling did not substitute for sampling over longer coastlines or broader
latitudes. Overall, this global live–dead comparison demonstrated that strandings
almost always provided better diversity information about extant cetacean
communities than live surveys; such archives are therefore relevant for
macroecological and palaeobiological studies of cetacean community change
through time.

Marine mammal mass strandings have occurred for millions
of years, but their origins defy singular explanations. Beyond human causes,
mass strandings have been attributed to herding behaviour, large-scale
oceanographic fronts and harmful algal blooms (HABs). Because algal toxins
cause organ failure in marine mammals, HABs are the most common mass stranding
agent with broad geographical and widespread taxonomic impact. Toxin-mediated mortalities
in marine food webs have the potential to occur over geological timescales, but
direct evidence for their antiquity has been lacking. Here, we describe an
unusually dense accumulation of fossil marine vertebrates from Cerro Ballena, a
Late Miocene locality in Atacama Region of Chile, preserving over 40 skeletons
of rorqual whales, sperm whales, seals, aquatic sloths, walrus-whales and predatory bony fish.Marinemammal
skeletons are distributed in four discrete horizons at the site, representing a
recurring accumulation mechanism. Taphonomic analysis points to strong spatial
focusing with a rapid death mechanism at sea, before being buried on a
barrier-protected supratidal flat. In modern settings, HABs are the only known
natural cause for such repeated, multispecies accumulations. This proposed
agent suggests that upwelling zones elsewhere in the world should preserve
fossil marine vertebrate accumulations in similar modes and densities.

What happens after the death of a marine tetrapod in
seawater? Palaeontologists and neontologists have claimed that large
lung-breathing marine tetrapods such as ichthyosaurs had a lower density than seawater, implying that
their carcasses floated at the surface after death and sank subsequently after
leakage of putrefaction gases (or ‘‘carcass explosions’’). Such explosions
would thus account for the skeletal disarticulation observed frequently in the
fossil record. We examined the taphonomy and sedimentary environment of
numerous ichthyosaur skeletons and compared them to living marine tetrapods,
principally cetaceans, and measured abdominal pressures in human carcasses. Our
data and a review of the literature demonstrate that carcasses sink and do not
explode (and spread skeletal elements). We argue that the normally slightly
negatively buoyant carcasses of ichthyosaurs would have sunk to the sea floor
and risen to the surface only when they remained in shallow water above a
certain temperature and at a low scavenging rate. Once surfaced, prolonged
floating may have occurred and a carcass have decomposed gradually. Our
conclusions are of significance to the understanding of the inclusion of carcasses
of lung-breathing vertebrates in marine nutrient recycling. The postmortem fate
has essential implications for the interpretation of vertebrate fossil
preservation (the existence of complete, disarticulated fossil skeletons is not
explained by previous hypotheses), palaeobathymetry, the physiology of modern
marine lung-breathing tetrapods and their conservation, and the recovery of human bodies from
seawater.

Marine
annelid worms of the genus Osedax exploit sunken vertebrate bones for
food. To date, the named species occur on whale or other mammalian bones, and
it is argued that Osedax is a whale-fall specialist. To assess whether extant
Osedax species could obtain nutrition from non-mammalian resources, we
deployed teleost bones and calcified shark cartilage at approximately 1000 m
depth for five months. Although the evidence from shark cartilage was inconclusive,
the teleost bones hosted three species of Osedax, each of which also
lives off whalebones. This suggests that rather than

being
a whale-fall specialist, Osedax has exploited and continues to exploit a
variety of food sources. The ability of Osedax to colonize and to grow
on fishbone lends credibility to a hypothesis that it might have split from its
siboglinid relatives to assume the bone-eating lifestyle during the Cretaceous,
well before the origin of marine mammals.

Sansom, R.S., Gabbott, S.E., and Purnell, M.A. 2010. Decay
of vertebrate characters in hagfish and lamprey (Cyclostomata) and the
implications fro the vertebrate fossil record. Proceedings of the Royal Society
B 278:1150-1157.

The
timing and sequence of events underlying the origin and early evolution of
vertebrates remains poorly understood. The palaeontological evidence should
shed light on these issues, but difficulties in interpretation of the
non-biomineralized fossil record make this problematic. Here we present an
experimental analysis of decay of vertebrate characters based on the extant
jawless vertebrates (Lampetra and Myxine). This provides a
framework for the interpretation of the anatomy of soft-bodied fossil
vertebrates and putative cyclostomes, and a context for reading the fossil
record of non-biomineralized vertebrate characters. Decay results in
transformation and non-random loss of characters. In both lamprey and hagfish, different
types of cartilage decay at different rates, resulting in taphonomic bias
towards loss of ‘soft’ cartilages containing vertebrate-specific Col2a1
extracellular matrix proteins; phylogenetically informative soft-tissue
characters decay before more plesiomorphic characters. As such, synapomorphic
decay bias, previously recognized in early chordates, is more pervasive, and
needs to be taken into account when interpreting the anatomy of any
non-biomineralized fossil vertebrate, such as Haikouichthys, Mayomyzon
and Hardistiella.

Exceptional preservation of soft-bodied Cambrian
chordates provides our only direct information on the origin of vertebrates1,2.
Fossil chordates from this interval offer crucial insights into how the
distinctive body plan of vertebrates evolved, but reading this pre-biomineralization
fossil record is fraught with difficulties, leading to controversial and
contradictory interpretations3,4. The cause of these difficulties is
taphonomic: we lack data on when and how important characters change as they
decompose, resulting in a lack of constraint on anatomical interpretation and a
failure to distinguish phylogenetic absence of characters from loss through decay3.
Here we show, from experimental decay of Amphioxus and Ammocoetes,
that loss of chordate characters during decay is non-random: the more
phylogenetically informative are the most labile, whereas plesiomorphic
characters are decay resistant. The taphonomic loss of synapomorphies and
relatively higher preservation potential of chordate plesiomorphies will thus
result in bias towards wrongly placing fossils on the chordate stem. Application
of these data to Cathaymyrus (Cambrian period of China) and Metaspriggina (Cambrian period of Canada) highlights the difficulties: these fossils cannot be
placed reliably in the chordate or vertebrate stem because they could represent
the decayed remains of any non-biomineralized, total-group chordate. Preliminary data suggest that this decay filter also
affects other groups of organisms and that ‘stem-ward slippage’ may be a
widespread but currently unrecognized bias in our understanding of the early
evolution of a number of phyla.

Remnants
of ophthalmosaurid ichthyosaurs recently discovered in the vicinity of the

Tyndall
Glacier in the Torres del Paine National Park of southern Chile
are extremely

abundant
and well preserved. After three field campaigns to the area, a total of 46
articulated and virtually complete ichthyosaur specimens, both adults and
juveniles, were tentatively assigned to four different species of
Ophthalmosauridae. Preservation is excellent and occasionally includes soft
tissue and embryos. The skeletons are associated with ammonites, belemnites,
inoceramid bivalves, and fishes as well as numerous plant remains. The enormous
concentration of ichthyosaurs is unique for Chile
and South America and places the Tyndall locality among
the prime fossil Lagerstätten for Early Cretaceous marine reptiles worldwide. The
deposit is Early Cretaceous (Valanginian–Hauterivian) in age and forms part of
a monotonous bathyal to abyssal sequence of the Late Jurassic to late Early
Cretaceous Rocas Verdes back-arc basin. In this region, the Tyndall ichthyosaur
population may have profited from cold upwelling currents that caused abundant
life at the shelf edge including masses of belemnites and small fish, the
preferred diet of ichthyosaurs. The abundance of almost completely articulated ichthyosaur
skeletons in the Tyndall area suggests that some animals fell victim to
episodic mass-mortality events caused by turbidity currents
traveling downslope through a submarine canyon. They lost orientation, drowned,
and were dragged into the deep sea by these turbulent high-energy gravity flows.
Their bodies ended up in an oxygen-deficient basin environment where they were
immediately embedded by the fine turbidite suspension fallout. The Tyndall
ichthyosaur locality thus combines characteristics of both concentration and
conservation Lagerstätten.

The
Bench 19 Bonebed at Bentiaba, Angola,
is a unique concentration of marine vertebrates preserving six species of
mosasaurs in sediments best correlated by magnetostratigraphy
to chron C32n.1n between 71.4 and 71.64 Ma. The bonebed formed at a
paleolatitude near 24°S, with an Atlantic width at that latitude approximating
2700 km, roughly half that of the current width. The locality lies on an
uncharacteristically narrow continental shelf near transform faults that controlled
the coastal outline of Africa in the formation of the South
Atlantic Ocean. Biostratigraphic change through the Bentiaba
section indicates that the accumulation occurred in an ecological time
dimension within the 240 ky bin delimited by chron 32n.1n. The fauna occurs in
a 10 m sand unit in the Mocuio Formation with bones and partial skeletons
concentrated in, but not limited to, the basal 1–2 m. The sediment entombing
the fossils is an immature feldspathic sand shown by detrital zircon ages to be
derived from nearby granitic shield rocks. Specimens do not appear to have a
strong preferred orientation and they are not concentrated in a strand line.
Stable oxygen isotope analysis of associated bivalve shells indicates a water
temperature of 18.5°C. The bonebed is clearly mixed with scattered dinosaur and
pterosaur elements in amarine assemblage. Gut contents, scavenging marks and
associated shed shark teeth in the Bench 19 Fauna indicate biological
association and attrition due to feeding activities. The ecological diversity
of mosasaur species is shown by tooth and body-size disparity and by d13C
analysis of tooth enamel, which indicate a variety of foraging areas and
dietary niches. The Bench 19 Fauna was formed in arid latitudes along
a coastal desert similar to that of modern Namibia
on a narrow, tectonically controlled continental shelf, in shallow waters below
wave base. The area was used
as a foraging ground for diverse species, including molluscivorus Globidens
phosphaticus, small species expected near the coast, abundant Prognathodon kianda, which fed on other mosasaurs at Bench 19, and
species that may have been transient and opportunistic feeders in the area.

Stringer, G.L., and King, L. 2012. Late Eocene shark
coprolites from the Yazoo Clay in northeastern Louisiana.
New Mexico Museum
of Natural History and Science Bulletin
57: 275-309.

Systematic,
long-term surface collecting of two sites in the marine sediments of the upper
Eocene Yazoo Clay (34.3 Ma) in Caldwell Parish, Louisiana,
has resulted in the procurement of nearly 1200 shark coprolites. A sample (n =
374 or approximately 30% of total) of the 1196 collected coprolites is
described in detail based on length, width, weight, density, coloration,
external features, internal features (when possible), and morphology. Two
primary morphological types, spiral and scroll, were recognized. Approximately
98.01% of the coprolites were classified as either spiral (556 specimens) or
scroll (617 specimens) based on external and internal morphological features.
X-ray analysis showed the coprolites to be composed of moderately crystalline
fluorapatite [Ca5(PO4)3F] with no compositional differences between the types.
An annotated review of the literature dealing specifically with chondrichthyan
coprolites was prepared. Prior studies at the sites produced extensive collections
of shark teeth (> 2500) and provided statistical abundance data on the shark
taxa. The shark tooth data, which provided occurrence and abundance, coupled
with modern information on shark size, anatomy, and excretory characteristics
allowed for a more specific identification of the shark coprolites as to
possible source animals. The most likely source animals for the spiral
coprolites were the lamniform Isurus praecursor and the carcharhiniform Abdounia
enniskilleni, while the scroll coprolites were most likely produced by the
carcharhiniform Carcharhinus gibbesi with the exception of several large
specimens, which may be related to Galeocerdo alabamensis. Some of the
coprolites had inclusions such as fish bones and scales that provided evidence
of the dietary habits of the sharks. The extensive and longitudinal nature of
this project has resulted in one of the most complete and exhaustive studies of
late Eocene shark coprolites from the Gulf
Coast.

We
present new geochemical and sedimentological data from marginal marine strata
of Penarth Bay,
south Wales (UK) to elucidate the origin of widespread but enigmatic
concentrations of vertebrate hard parts (bonebeds) in marine successions of
Rhaetian age (Late Triassic). Sedimentological evidence shows that the
phosphatic constituents of the bonebeds were subjected to intense
phosphatization in shallow current dominated settings and subsequently reworked
and transported basinward by storms. Interbedded organic-rich strata deposited
under quiescent and poorly oxygenated conditions record enhanced phosphorus
regeneration from sedimentary organic matter into the water column and probably
provided the main source of phosphate required for heavy bonebed clast
phosphatization. The stratigraphically limited interval showing evidence for oxygen
depletion and accelerated P-cycling coincides with a negative 4‰ organic carbon
isotope excursion, which possibly reflects supra-regional changes in carbon
cycling and clearly predates the ‘initial isotope excursion’ characterizing
many Triassic–Jurassic boundary strata. Our data indicate that Rhaetian
bonebeds are the lithological signature of profound, climatically driven
changes in carbon cycling and redox conditions and support the idea of a
multi-pulsed environmental crisis at the end of the Triassic, possibly linked
to successive episodes of igneous activity in the Central
Atlantic Magmatic
Province.

Takukawa,
Y. 2014. A dense occurrence of teeth of fossil "mako" shark ("Isurus"
hastalis: Chondrichthyes, Lamniformes), associated with a
balaenopterid-whale skeleton of the late Miocene Pisco Formation, Peru,
South America. Bulletin of the Gunma
Museum of Natural History 18:77-86.

Sixteen fossil shark teeth were found in close contact
with a balaenopterid-whale skeleton of the Late Miocene Pisco Formation in Peru, South
America. This whale skeleton (GMNH-PV 159) was excavated in Aguada de Lomas of western Arequipa in 1990, and exhibited in Gunma Museum of Natural
History, Japan, after 1996. All teeth have relatively large and triangular
shaped crowns. The cutting edge is smooth
and almost straight in profile. Their roots are bulky and
stout with long or expanded lobes. These characteristics indicate that all
teeth are identified to fossil ‘mako’
shark (“Isurus”hastalis). And the
variety of the shape in each tooth implies difference of tooth position in its
jaw. The duplication of the teeth at two positions (anterior tooth and intermediate tooth)
and the difference of the crown size of anterior
teeth suggest that the minimum number of shark individuals which had preyed on
the whale is two. And one of them might be smaller than the other one. In
addition, it is recognized that one of the sharks sank its upper lateral tooth
into the whale skull bone.

Combined
sedimentological and taphonomical study of the siliciclastic sequence of the Tērvete
Formation in the stratotypical area was aimed at revealing the formation of the
three oryctocoenoses discovered and related structural and textural features of
the deposits, as well as at detailed observation of the taphonomical
peculiarities of the obtained palaeontological material. The fossil vertebrate
assemblage is represented by 14 taxa comprising placoderms, acanthodians,
sarcopterygians and actinopterygians. The three oryctocoenoses, first
recognized in 2010, differ in the proportions of repeatedly buried material, in
the number and degree of preservation of small and fragile skeletal elements,
as well as in the evaluated current velocity and the transportation distance.
Sedimentary concentrations of marine vertebrate remains, dominated by the
antiarchs Bothriolepis ornata and B.
jani, have been formed under the influence of fluvial and tidal
processes in the shallow-water environment, deltaic or estuarine settings.
Elongated placoderm and sarcopterygian bones are probably better indicators of
the palaeoflow direction than acanthodian spines or sarcopterygian teeth.

Sharks are known to have been ammonoid predators, as
indicated by analysis of bite marks or coprolite contents. However, body fossil
associations attesting to this predator–prey relationship have never been described
so far. Here, I report a unique finding from the Late Jurassic of western France: a complete specimen of the Kimmeridgian ammonite Orthaspidoceras bearing one tooth
of the hybodont shark Planohybodus. Some possible tooth puncture marks
are also observed. This is the first direct evidence of such a trophic link between these two major
Mesozoic groups, allowing an accurate identification of both organisms.
Although Planohybodus displays a tearing-type dentition generally
assumed to have been especially adapted for large unshelled prey, our discovery
clearly shows that this shark was also able to attack robust ammonites such as
aspidoceratids. The direct evidence presented here provides new insights into
the Mesozoic marine ecosystem food webs.

A
dense assemblage of fossil isopod crustaceans (Brunnaegatomhurleyi
Wilson, sp. nov.) from the Lower Cretaceous
(Albian) Toolebuc Formation of Queensland, Australia,
has been found within the carcass of a large actinopterygian fish, Pachyrhizodus
marathonensis (Etheridge). Preservation of fine anatomical details supports
referral to the genus Brunnaega Polz, which is herein reassigned to the
family Cirolanidae. Furthermore, placement of this taxon within the cirolanid
subfamily Conilerinae Kensley and Schotte is significant because the group
includes modern species that are well known as voracious scavengers. This
isopod–fish association represents the oldest unequivocal evidence of
scavenging by Mesozoic cymothoidean isopods on a large vertebrate carcass.

A
well-preserved fish skull from late Albian deposits of the Allaru Mudstone near
Richmond in Queensland
displays a conspicuous V-shaped pattern of indentations, punctures and
depression fractures consistent with a vertebrate bite trace. This is the first
direct evidence of trophic interaction between vertebrates within an Early
Cretaceous marine ecosystem from Australia.
The specimen is taxonomically referable to the large bodied (ca 1m snout–tail
length) ichthyodectiform Cooyoo australis, but the size and spacing of
the tooth marks is incompatible with attack by a conspecific
individual. The lack of osseous growths concordant with healing also suggests
that the bite occurred shortly before or after the animal’s death. Comparison
with the dentitions of other coeval vertebrates indicates compatible tooth arrangements
in longirostrine amniote predators such as polycotylid plesiosaurians,
ornithocheiroid pterosaurs and especially the ichthyosaurian Platypterygius.
The implications of this as a potential predator–prey association are that
Early Cretaceous actinopterygians occupied middle-level trophic niches and were
in turn consumed by higher-level
amniote carnivores, similar to many extant marine vertebrate communities of
today.

Reports of pathological ichthyosaur fossils are very
rare. The identification of a series of healed cuts and an associated gouge on
the lower jaw of an adult (ca. 5 metres body length) Platypterygius specimen
from the Lower Cretaceous of Australia is therefore significant, because it
constitutes direct evidence of bite force trauma sustained during the life of
the animal. Based on the close spacing and nonlethal facial positioning of the
wounds, they were probably not inflicted by a predator. Alternative explanations
might include an accidental aggressive encounter with another large vertebrate,
or perhaps an intraspecific interaction such as during courtship or combat over
food, mates, or territory.

Small,
light-brown and beige cylindrical structures found in the lower Famennian
(Upper Devonian) shales and marls of the Holy
Cross Mountains
area, central Poland,
have been investigated for the first time. Their compact, pellet-shaped morphology
and the presence of various fossil fragments scattered within the phosphatic
groundmass clearly indicate that they are coprolites. The coprolite inclusions
are dominated by arthropod cuticle fragments followed by fish remains, one
conodont, and one scolecodont. The arthropod cuticle fragments are represented
by the crustacean-like thylacocephalan Concavicaris and three other
different types of arthropods of uncertain affinity. The presence of some
conical fragments resembling telsons from phyllocarid crustaceans suggests that
some of the cuticle fragments may belong to that group of arthropods. The fish
remains mainly consist of actinopterygian paleoniscoid scales and
sarcopterygian teeth. Taking both fossil and facies characteristics into
account, it is clear that the coprolites originated from a carnivorous pelagic
fishes that hunted other fishes and swimming arthropods. Surprisingly, similar
faunal contents consisting of paleoniscoid fishes, Concavicaris
arthropods, and conodonts occur in situ within the body cavities of the
Famennian cladoselachian sharks in the Cleveland Shale, Ohio.
Such a coincidence suggests that at least some of the Famennian coprolites from
Poland may have
also been produced by pelagic carnivorous sharks. The preservation of defecated
remains was influenced by an
interplay between an oxygen-deficient benthic environment devoid of
bioturbators and scavengers and rapid, microbially-driven phosphatization.

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About the Coastal Paleontologist

I am a Ph.D. student in the Geology program at the University of Otago, New Zealand, working with R. Ewan Fordyce on Oligocene fossil cetaceans from the South Island. My dissertation research focuses on eomysticetid baleen whales (the earliest known toothless baleen whales), and my project will involve description, phylogenetic analysis, and assessing their feeding ecology. I received my master's degree in May 2011 from Montana State University, where I studied the taphonomy of late Neogene marine vertebrates from the Purisima Formation of Northern California. I am currently involved in studying fossil marine mammals from the Miocene, Pliocene, and Pleistocene of California and Oregon, and am a Research Associate of the University of California Museum of Paleontology (UC Berkeley).